A. Field of the Invention
The present invention relates to the field of belt sanders that are adapted for pipes, shafts, and cylindrical objects.
B. Prior Art
The Brandli et al. patent (U.S. Pat. No. 3,895,463) discloses an apparatus for buffing and polishing the entire outer surface of cylindrical tubing. However, this patent is not portable, and does not utilize a sanding belt that is draped over the exterior surface of a cylindrical object. This patent also uses pneumatic circuits and hydraulic motors to transmit power to the moving parts.
The Gardner patent (U.S. Pat. No. 5,038,525) discloses a pipe and polishing apparatus and method which comprises a cradle having an open section and a pair of pivotable doors covering the open sections and adapted to move between an open, pipe receiving position and a closed, pipe polishing position, the doors biased to remain in an open, pipe receiving position. This patent does not utilize a sanding belt that is draped over the exterior surface of a cylindrical object with a housing that contains an electrical motor, as opposed to a device that attaches to the chuck of a standard drill.
The Kadinger patent (U.S. Pat. No. 6,813,797) discloses an adjustable wire brush tool for cleaning either the inside or the outside end of a copper pipe. This device attaches to the chuck of a standard drill, and is not expandable to accommodate the various diameters of cylindrical objects.
The Zepp patent (U.S. Pat. No. 5,649,852) discloses a reciprocating and rotating sanding apparatus which has an expandable/adjustable sanding sleeve. However, this device requires connection to a drill press, and utilizes a rotary drum sanding device that does not drape over the exterior surface of a cylindrical object.
The Miner patent (U.S. Pat. No. 4,600,444) discloses a pipe exterior end cleaning device comprising a plurality of rotating brushes. However, this device is not portable nor does it drape a sanding belt over the exterior.
The Burrell patent (U.S. Pat. No. 4,869,026) discloses a belt sander which is powered by an electric motor and polishes metal or wood work pieces to a cylindrical or curved shape. However, this patent requires an exterior motor to provide the mechanical means to rotate the sanding belt.
The Helbig patent (U.S. Pat. No. 2,759,305) discloses a portable polishing and abrading machine that is not designed to drape a sanding belt over the exterior surface of a cylindrical object.
The Tomo et al. patent (U.S. Pat. No. Des. 229,616) illustrates a design for a portable polishing device that is not directed to sanding and does not drape a sanding belt over the exterior surface of a cylindrical object.